1. Field of the Invention
The present invention relates to a control system for a vehicle that can run in an unmanned state and in a manned state, and particularly to a technique to reduce a vehicle exterior noise caused due to an internal combustion engine during unmanned running.
2. Description of Related Art
There has been known a vehicle including an internal combustion engine and a vehicle control device that can perform unmanned running and manned running. In such a vehicle, a vehicle control device that performs an unmanned automatic operation instead of an operation by a driver is proposed. For example, a vehicle control device of Japanese Patent Application Publication No. 2012-126193 (JP 2012-126193 A) includes an internal combustion engine ECU that controls an output of an internal combustion engine of a vehicle, a steering ECU that controls a rotation direction and a rotation angle of steering of the vehicle, and a camera that takes images around the vehicle. In an automatic parking system provided outside the vehicle, a simulated accelerator lever operation and a simulated steering operation are performed based on images taken by the camera and wirelessly transmitted therefrom, as follows: based on information on a display that displays a vehicle image subjected to image processing and car-park images such as a parking space image and a parking vehicle image indicative of another vehicle that has been already parked in a parking space, the vehicle image on the display is parked in an empty parking space by an operator outside the vehicle. Based on automatic operation information formed by the simulated operation by the operator, a control on the internal combustion engine via the internal combustion engine ECU and a steering control via the steering ECU are performed by the vehicle control device, so that running to a parking space is performed by an unmanned automatic operation. Hereby, a burden of a driving operation of a driver at the time of parking is reduced.
In the meantime, the unmanned automatic operation described above may be performed in such a situation that the vehicle is moved from a garage in the early morning, for example. Further, a remote operation in which an unmanned vehicle is remote-controlled by an operation outside the vehicle from a control room or the like may be performed in such a situation that packages are conveyed or the vehicle is moved in a factory in the middle of the night. Such unmanned running in the early morning or in the middle of the night may have a problem with a vehicle exterior noise, which is a noise emitted outside the vehicle due to the internal combustion engine, for example.